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91.
目的:统计分析中药注射剂种类及其处方饮片的原料药材,为中药注射剂上市后再评价及原料药材生产提供参考。方法:从国家药品监督管理局网站获取已上市中药注射剂数据,从国家食品药品监督管理局南方医药经济研究所米内网数据库中获取2017年中国城市公立医院13个畅销中药注射剂数据,从2015版《中华人民共和国药典》(以下简称《中国药典》)获取其收录中药注射剂数据,统计分析其种类、成分、功能主治、给药方式和处方饮片的原料药材。结果:当前已上市中药注射剂共134种,涉及处方饮片的原料药材158种,药材数量以1味和2味居多,部分药材2015版《中国药典》未收录,少数药材历版《中国药典》均未收录;功能主治方面用于治疗心脑血管疾病的中药注射剂种类最多,同时销售额前三的中药注射剂也都用于治疗心脑血管疾病。结论:中药注射剂种类繁多,绝大部分中药注射剂处方饮片的原料药材数量较少,成分相对简单,但原料药材来源复杂,药材数量与给药方式间并无明显关系,部分药材标准无法满足中药注射剂安全性需求,有待完善;用于治疗心脑血管疾病的中药注射剂种类和销售额均为最多,主要原料药材丹参和红花等需要重点关注。  相似文献   
92.
急性肺损伤的氧化作用与抗氧化研究进展   总被引:1,自引:0,他引:1  
赖荣德  梁子敬 《国际呼吸杂志》2006,26(12):924-927,931
急性肺损伤(ALI)是临床常见的呼吸系统急症,发病率高,确切发病机制不甚明确,临床治疗效果欠佳。本文对近几年ALI的氧化作用研究和抗氧化对ALI的治疗作用和相关研究进展,以及抗氧化作用对ALI的治疗前景作一综述。  相似文献   
93.
BACKGROUND AND PURPOSE: There is concern about the increase of radiation-induced malignancies with the application of modern radiation treatment techniques such as intensity-modulated radiotherapy (IMRT) and proton radiotherapy. Therefore, X-ray scatter and neutron radiation as well as the impact of the primary dose distribution on secondary cancer incidence are analyzed. MATERIAL AND METHODS: The organ equivalent dose (OED) concept with a linear-exponential and a plateau dose-response curve was applied to dose distributions of 30 patients who received radiation therapy of prostate cancer. Three-dimensional conformal radiotherapy was used in eleven patients, another eleven patients received IMRT with 6-MV photons, and eight patients were treated with spot-scanned protons. The treatment plans were recalculated with 15-MV and 18-MV photons. Secondary cancer risk was estimated based on the OED for the different treatment techniques. RESULTS: A modest increase of 15% radiation-induced cancer results from IMRT using low energies (6 MV), compared to conventional four-field planning with 15-MV photons (plateau dose-response: 1%). The probability to develop a secondary cancer increases with IMRT of higher energies by 20% and 60% for 15 MV and 18 MV, respectively (plateau dose-response: 2% and 30%). The use of spot-scanned protons can reduce secondary cancer incidence as much as 50% (independent of dose-response). CONCLUSION: By including the primary dose distribution into the analysis of radiation-induced cancer incidence, the resulting increase in risk for secondary cancer using modern treatment techniques such as IMRT is not as dramatic as expected from earlier studies. By using 6-MV photons, only a moderate risk increase is expected. Spot-scanned protons are the treatment of choice in regard to secondary cancer incidence.  相似文献   
94.
Radiolabeled octreotide analogs (Oct) and metaiodobenzylguanidine (MIBG) offer 2 different approaches for imaging and targeting metastatic gastroenteropancreatic neuroendocrine tumors (GEP-NET). Despite successful establishment of the revised World Health Organization (WHO) classification, which distinguishes between low- and high-grade malignant GEP-NET, there is a lack of scintigraphic studies comparing uptake behavior on the basis of this categorization. This study aims to define predisposing factors of tracer uptake for both imaging principles implementing the updated tumor criteria of the current WHO classification. METHODS: Fifty-seven consecutive patients with histologically confirmed metastatic GEP-NET evaluated with both 111In-pentetreotide and 123I/131I-MIBG scintigraphy were included in this study. Intensity of tracer uptake was graded according to the different metastatic regions. Patients were classified as overall positive when avid uptake in the clinically relevant tumor lesions was present. Correlation was tested between the proportion of positive patients and tumor origin, function, and malignancy. RESULTS: Overall, 52 patients (91.2%) were Oct positive and 28 patients (49.1%) were MIBG positive. The proportion of tracer-positive patients was significantly higher (P < 0.05) in low-grade malignant tumors for both tracers and in functioning as well as in gastroenteral NET for MIBG. Five patients were negative for both tracers. None of the Oct-negative patients proved to be MIBG positive. CONCLUSION: Oct affinity is observed with high frequency throughout the subgroups of metastatic GEP-NET, whereas corresponding MIBG uptake is overall less prevalent and more group dependent. Tumor differentiation significantly impacts both Oct and MIBG uptake, whereas functionality predisposes only for MIBG accumulation. Though clearly inferior to Oct-based radioimaging in most GEP-NET, MIBG achieves a remarkable rate of radioligand accumulation in functioning midgut enterochromaffin cell metastases (>80% of patients positive). These results may have implications for patient management and potentially for selection and performance of targeted therapy.  相似文献   
95.
1.318 μm近红外激光视网膜损伤阈值研究   总被引:2,自引:2,他引:0  
目的研究1·318μm激光对视网膜的损伤效应,确定其损伤阈值。方法用输出波长1·318μm的Nd∶YAG激光为照射光源,固定照射时间0·2s,以不同剂量的激光照射散瞳后的家兔(25只)和大鼠(28只)眼睛,照射光斑直径分别为5mm和2mm,于照后1h和24h观察视网膜损伤发生率,用加权概率单位法计算损伤发生率为50%时所对应的激光剂量,即损伤阈值ED50。并于照后24h对损伤视网膜做病理切片观察。结果1·318μm激光致家兔和大鼠视网膜损伤的阈值角膜剂量分别为13·7J/cm2和10·4J/cm2,阈值角膜能量分别为2·69J和0·33J。受损视网膜可见清晰的白色凝固斑,损伤重者累及视网膜全层。结论1·318μm激光可导致家兔和大鼠视网膜损伤,损伤阈值ED50分别为13·7J/cm2和10·4J/cm2。  相似文献   
96.
During skeletal development the two ossification centers of the odontoid process are separated from the corpus of the axis by a subdental synchondrosis. This synchondrosis is thought to close and disappear spontaneously in adolescence although this has never been studied in detail. The basis of the dens is of clinical relevance as type II dens fractures are located here. To characterize the morphological architecture of the axis with particular attention to the subdental synchondrosis, the complete axis was harvested from thirty age-matched and gender-matched patients of the three different age groups at autopsy. The subdental synchondrosis and the bone structure of the dens, the basis of the dens and the body of C2 were analyzed by radiography, histology and quantitative histomorphometry. At the macroscopic level the persistency of the subdental synchondrosis in the adult cervical spine was detected in 87% (26 of 30) of the specimens. Histomorphometry revealed a residual disc blastema with an average size of 25.8% of the sagittal depth of the basis of the dens at this level. Bony integration of the synchondrosis was poor throughout all ages. Histologically a cartilaginous matrix composition of the subdental synchondrosis persisted throughout all groups. The trabecular microarchitecture demonstrated a significant reduction of bone volume and trabecular number as well as an increased trabecular separation within the basis of the dens as compared to the corpus or the dens of C2. This histomorphometric data regarding a poor integration of the synchondrosis into the trabecular network and the reduced bone mass within the basis of the dens might offer a previously underestimated explanation for the occurrence of type II dens fractures and their association with pseudoarthrosis, respectively.Matthias Gebauer and Christian Lohse contributed equally to this study and therefore share first authorship.  相似文献   
97.
Low molecular weight heparins are widely used in the prophylaxis and treatment of thrombotic disorders. The effect of low molecular weight heparins on coagulation was examined ultrastructurally in an animal model. A test and a control group was formed, each consisting of five rabbits. Nadroparine (225 Institute of Chaoy Unit/kg twice daily) was applied to the test group for 10 days. The control group received 1 ml saline solution subcutaneously. Blood and vascular tissue samples collected at the end of the 10th day were evaluated under a JEM 100 B electron microscope. Platelet degranulation and agglutination was observed in the control group. Fibrin materials were detected in the cytoplasms and surroundings of degranulated platelets. Erythrocyte accumulation was remarkable on the vascular endothelium with intact coagulation periods. In the test group, outer membranes of platelets, hyalomere, and granular structures in the granulomeres were detected to be nearly intact. There were rare erythrocytes in the large vascular lumens. The aggregation phase had occurred but no agglutination was detected. Nadroparine seems to preserve consistency of lipoprotein membranes of platelets and granular structures containing enzymes, which contribute to the coagulation mechanisms.  相似文献   
98.
99.
目的 初步探讨居室内花岗岩石材的放射性对小鼠生存和生殖的影响。方法 用γ能谱分析方法按国家标准测定和筛选A、B、C、D 4类放射性不同的花岗岩石材,并置放在小鼠饲养笼内。饲养期间用两种方法测量动物室的氡浓度.随机选择健康刚断奶的小鼠96只,分别置于4类放射性不同的动物饲养室内饲养120 d,让其自然交配并生育后代。观察分析P代、F1代、F2代小鼠的生育和生存情况.结果 4类小鼠饲养室的石材外照射指数比内照射指数高。小鼠饲养120 d后,P代和F1代的受孕率、流产率和不育率各组间差异无统计学意义(P>0.05)。F1代各实验组间母鼠生育活仔鼠数差异有统计学意义(P<0.001),并随着小鼠饲养室内的放射性增高而幼鼠的存活数显著性下降(P<0.001)。结论 动物饲养室内花岗岩石材放射性核素释放的γ射线对动物机体的影响较室内氡大;提示了花岗岩石材不同放射性对小鼠的生育和幼鼠的存活产生不同程度的影响。  相似文献   
100.
Abstrakt 1. Ein nicht ausgefülltes und nicht unterschriebenes Aufkl?rungsformular in der Krankenakte bildet ein Indiz nicht für, sondern gegen die Durchführung eines Aufkl?rungsgespr?chs. 2. Wenn vor dem ?rztlichen Eingriff überhaupt keine Aufkl?rung erfolgt, genügt für den Beginn der Verj?hrung eines auf eine Aufkl?rungspflichtverletzung gestützten Anspruchs die Kenntnis vom Eintritt schwerwiegender Komplikationen. Nicht erforderlich ist das Wissen, dass sich ein typisches Risiko des Eingriffs verwirklicht hat.  相似文献   
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